coreboot-kgpe-d16/payloads/libpayload
Julius Werner bf27391da5 libpayload: Add LZ4 decompression algorithm
This patch adds support for the LZ4 decompression algorithm to
libpayload. It's what all the cool kids are using for decompression
these days and has many interesting advantages over LZMA (and everything
else I know of): blazing fast decompression (20(!) times faster than
LZMA, twice as fast as LZO on my Cortex-A72), no memory requirements on
decompression, and possibly in-place decompression support. It pays for
that with a lower compression ratio (about 50% larger compressed size
than LZMA, 10% larger than LZO for an ARM64 Linux kernel binary), but
the boot time math still works in its favor for our IO speeds.

This patch only adds the raw decompression functions for use by external
payloads, we can later try integrating them in CBFS. It copies the
decompression code itself unmodified from the upstream LZ4 library at
github.com/Cyan4973/lz4 which will hopefully make it easy to update. The
frame format parsing is reimplemented since the upstream version looks
unnecessarily complex and unreadable for our needs.

BRANCH=smaug
BUG=chrome-os-partner:32184
TEST=With other patches, booted ARM64 kernel that got compressed from
15M to 5.1M and decompresses in 44ms.

Change-Id: I65bdc4b2b19bd51c7b7e17a4e4b79da301a2a014
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: f8a1fc996d5b0234d07f567fa8163d0f802d5144
Original-Change-Id: I15c0620da05561ade2552b15ffdf6bb3afd7eb26
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/282743
Original-Reviewed-by: Stefan Reinauer <reinauer@google.com>
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/10845
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2015-07-09 00:10:16 +02:00
..
arch cbfs: define libpayload_init_default_cbfs_media weakly 2015-07-06 09:42:12 +02:00
bin libpayload: arch/mips: Add basic MIPS architecture support 2015-03-21 11:07:50 +01:00
configs libpayload: update defconfigs 2015-07-08 10:25:11 +02:00
crypto libpayload: Make Kconfig bools use IS_ENABLED() 2015-06-30 18:55:15 +02:00
curses libpayload: Make Kconfig bools use IS_ENABLED() 2015-06-30 18:55:15 +02:00
drivers libpayload: usb: dwc2: support interrupt transfer 2015-07-06 09:40:02 +02:00
gdb Remove address from GPLv2 headers 2015-05-21 20:50:25 +02:00
include libpayload: Add LZ4 decompression algorithm 2015-07-09 00:10:16 +02:00
libc libpayload: Make Kconfig bools use IS_ENABLED() 2015-06-30 18:55:15 +02:00
libcbfs libpayload: Make Kconfig bools use IS_ENABLED() 2015-06-30 18:55:15 +02:00
liblz4 libpayload: Add LZ4 decompression algorithm 2015-07-09 00:10:16 +02:00
liblzma lzma: Return correct amount of decompressed bytes 2015-07-06 09:40:37 +02:00
libpci Remove empty lines at end of file 2015-06-08 00:55:07 +02:00
sample Remove empty lines at end of file 2015-06-08 00:55:07 +02:00
tests Remove empty lines at end of file 2015-06-08 00:55:07 +02:00
util/xcompile libpayload: Add compiler switch 2015-07-06 18:25:52 +02:00
Doxyfile Run doxygen -u on doxygen configuration files 2010-06-28 10:40:38 +00:00
Kconfig libpayload: Add LZ4 decompression algorithm 2015-07-09 00:10:16 +02:00
LICENSES libpayload: Add LZ4 decompression algorithm 2015-07-09 00:10:16 +02:00
LICENSE_GPL libpayload: Introduce new Kconfig to explicitly allow GPL code 2015-01-09 07:06:27 +01:00
Makefile libpayload: architecture mapping is now done in xcompile 2015-07-06 18:27:01 +02:00
Makefile.inc libpayload: Add LZ4 decompression algorithm 2015-07-09 00:10:16 +02:00
README Remove empty lines at end of file 2015-06-08 00:55:07 +02:00

README

-------------------------------------------------------------------------------
libpayload README
-------------------------------------------------------------------------------

libpayload is a minimal library to support standalone payloads
that can be booted with firmware like coreboot. It handles the setup
code, and provides common C library symbols such as malloc() and printf().

Note: This is _not_ a standard library for use with an operating system,
rather it's only useful for coreboot payload development!
See http://coreboot.org for details on coreboot.


Installation
------------

 $ git clone http://review.coreboot.org/p/coreboot.git

 $ cd coreboot/payloads/libpayload

 $ make menuconfig

 $ make

 $ sudo make install (optional, will install into /opt per default)

As libpayload is for 32bit x86 systems only, you might have to install the
32bit libgcc version, otherwise your payloads will fail to compile.
On Debian systems you'd do 'apt-get install gcc-multilib' for example.


Usage
-----

Here's an example of a very simple payload (hello.c) and how to build it:

 #include <libpayload.h>

 int main(void)
 {
     printf("Hello, world!\n");
     return 0;
 }

Building the payload using the 'lpgcc' compiler wrapper:

 $ lpgcc -o hello.elf hello.c

Please see the sample/ directory for details.


Website and Mailing List
------------------------

The main website is http://www.coreboot.org/Libpayload.

For additional information, patches, and discussions, please join the
coreboot mailing list at http://coreboot.org/Mailinglist, where most
libpayload developers are subscribed.


Copyright and License
---------------------

See LICENSES.